This invention relates to a hollow stabilizer for a vehicle, which is made from a single pipe and has a torsion section coupled to a vehicle frame, curved sections each integrally extending from each end of the torsion section and arm sections each integrally extending from each curved section and having a free end coupled to a wheel suspension.
Stabilizers of this sort have hitherto been used for the purpose of improving the feel of riding and the stability of vehicles such as automobiles by improving the tilting of the vehicle caused at the time of the turning due to centrifugal forces at this time and unbalance of the ground pressure on the opposite side wheels that is caused at such time. Usually, the stabilizer has a construction constituted by a single metal pipe, which has a central torsion section terminating at the opposite ends in curved sections defining an obtuse angle and terminating in turn in respective arm sections. The torsion section is coupled to the frame of the automobile or the like via mounting members such that it extends in the lateral direction, while the arm sections are coupled to the opposite sides of a vehicle suspension via coupling sections provided at their free ends. Mounted in this way, the stabilizer acts to suppress the outward tilting of the vehicle and also the floating of the inner wheels at the time of the turning of the vehicle with the twisting of the torsion section, the bending of the arm sections and the twisting and bending of the curved sections. Thus, various characteristics of the stabilizer have to be suitably set by taking the weight of the vehicle, the height of the centroid thereof, the construction of the wheel suspension, etc. into consideration.
In order to reduce the weight of the stabilizer it has been in practice to manufacture the stabilizer from a metal pipe. In this case, however, if the pipe thickness is excessively reduced for increasing the weight reduction factor, the fatigue strength is reduced. Accordingly, it has been proposed to appropriately set the outer diameter and thickness of the pipe to meet the maximum load stress. However, such a hollow stabilizer has a uniform outer diameter and a uniform thickness over its entire length, and some portions of it do not require the preset thickness; that is, they have an extra thickness, so that there is still some room for improvement regarding weight reduction.
The invention developed from research and investigations concerning the distribution of the load applied to the stabilizer, and its primary object is to provide a hollow stabilizer for a vehicle, which is light in weight and in which the material is adequately distributed to prevent reduction of the fatigue strength.